Apparatus for detinning tin-scrap.



I PATBNTED JULY 9, 1907. m LEITGH. APPARATUS FOR DETINNING TIN SCRAP.

APPLIOATIOI FILED FEB. 17, 1900.

3 SHEETS-SHEET 1- 1m1, mm f A w m m 11.. .A- A A I ca-m m No.85 9,565. 1 PLTENTED JULY9,1-907.

- 1M. LEITGH;

APPARATUS FOR DETINNING TINYSGRAP upmonmn runn 1'33. 1-1, 1000.

8 SHEETS-BEBE? PATENTED JULY 9, 1907.

Mi LEITGH. APPARATUS FOR DBTINNING TIN SCRAP.

. APPLICATION TILED FEB. 17, 1908.

3 BEEETB-SKEEI 3. v

qwvbnmea plates.

UNITED srirrns MEREDITH LEITCH. OF lELlQ-rlilfi'lil, NEW .ll'lltS PATENT .oFFIoE;

EY, i

OF JERSEY CITY, NEW JlLR-SE IZ A COR?ORATION OF NEW JERSEY APPARATUS FUR DE'IINNING- TIN-SCRAP.

Specification f Letters Patent.

iatented July 9, 1907- Application filed February 17,1906; Serial No. 301,585. a A

To all whom it mag concern:

Be it known that I, Mnnnorru'l enrrcn, a citizen of.

i the United States, residing at Elizabeth, Union county,

for removing the tin coating from scrap tin, includingtin cuttings, tin cans, and the like.

In detinniug, plants as now constituted, scrap tin is usually deposited in baskets which are then immersed in electrolytic baths, theresubjected to the action of an electric current, and subsequently removed by hand or by hoists of some suitable construction, after which the detinned. or black scrap is immersed in Wash tanks; the apparatus requiring or the handling of the scrap during this process hoists, baskets, tanks, cars, trucks and turn-tables, and manual labor at the various stages.

The object of my invention is to produce an eflicient apparatus which shall. be continuous in its operation and shall eliminate all manual labor in the 'detinni'ng process, except that required toieed the scrap into a hopper and collect the tin powder from the cathode It further has for its object to reduce the cost of the electrolyteby thorough draining of the scrap and by thorough washing, and to reduce the cost of'regenerating the electrolyte by reducing its exposure to the atmosphere, thus preventing the absorption of carbonic acid.

It further has for it'sobject to reduce the cost of electric energy by providing better electrical connections and more effective Working relations and a lower resistance between the elements of the bath.

It further has for its object to reduce the cost of fuel comparatively small exposed surface.

' "It further has for its object to effect a more complete Y detinning'by subjecting the-scrap in one bath to the same'conditions of current strength and heatand almost uniform position with relation to fiowol the electric current and electrolyte.

It further has for its object'to produce an easily collect'ibletin powder almost free from foreign matter by depositing it only upon removable cathode plates, the

refuse being allowedto precipitate to the bottom of the tank.

The following is a description of the apparatus em- 'bodying my invention, reference beinghad to the ac companying drawings, in which Figure 1 shows my apparatus partly in vertical section and partly in side elevatirm. Fig. 2 represents a, horirontal section of the same on the line a'a Fig. 1.

' Fig. .l represents'an. end elevation with parts broken away. Fig. 4 represents a horizontal section of the apparatus on the line y y, Fig. 1. Figs. 5 and (i rcprosent diagrammatically in plan and side elevation the system embodying theelectrolyfic and washing baths.

Referring more particularly to the drawings, A represents a. tank, preferably of iron, designed to rest on the floor or the floor of a pit, and eleetrically'insulatvd at a n so as to remain neutral with reference totluelectric circuithereinafter described, even When that circuit is grounded. The top of the tank is about level with the floor 13 of the tin scrap room The tank A contains 111 o electrolyte C, which is preferably a solution of caustic soda, heated to about Centigrade, such as has heretofore been used in electrolytic detinning. The tank A is provided with an inlet D and an outlet E, and supply and return pipes D and E disconnected or othelvvise insulated therefrom for the circulation of the heated electrolyte. There is also a draw-off pipe -F at the bottom of the tank for completely emptying the same, and

SS] UN 0 R T0 .ULERIOAN (1A COM PANY a clean-out door G for removing the precipitated waste. Within this tank there is a stationary receiver 11, which in its preierred form, is a XI -shaped basket or tube, as

shown, preferably of iron,.which is to receive and sup:

The sides of thebasket or tube are made of s root .metal, perforated as zit-J11. The curved bottom is made of sheet metal, but is imperforate so as to prevent. the sifting out of particles that may be present. The ends H are preferably of perforated cast metal having flanges h to which the perforated sides of the basket H are secured in such a way as to avoid any roughness on the inside of the tube or basket. 7 These ends are provided with raised portions .J in which are formed grooves to receive conveyor chains K. The grooves at the lower part of the tube are curved as shown at J and the inner curved surfaces of the'grooves aredormed by sniootlnrimmed wheelsL'mou'nted on the outside oithe tubc'or basket H, but having their rims pr0ject-' ing through slots in the castings in such a way that the rims of the wheels form the inner curved surfaces of the grooves, thus providingnieans' for turning and L are mounted insuitable bearings'Ms M carried by the basket H. Fastened to the chains are T- bars N N,'

which, when thechainsarein motion, serve to convey J the scrap down and up through the-U-shapedbasket I and through an impcriorate upward extensionfl? of v the tube and over the top to the discharge chute H from which the scrap will'glide by gravity into the black scrap :ouveym- O.

The conveyor is designed to receive the detinned or black scrapfrorn a number ef baths as they discharge, and deliver it to a washer or series of washers similar in eonstruction to the dcti' ring bath, or to such point as I clectrieity. .l.heca thodes S, i and S canthus be remay be desired; In passing to the discharge chute the conveyor chains pass over sprocket wheels P, which project through slots in the castings in the same man- -ner as do the wheels Land thus form the inner curved surfaces of. the grooves at the points where they are located. The sprocket teeth engage the chains and impart motion thereto, power being supplied from any' suitable source. .The conveyor chains, after leaving the disohargechute, pass over idlers Q and R, supported on woodenheains orotherwiseinsiilated, and- -'then return to the U-shaped basket H. Immersed in:

theelectrolyte within the tank are three cathodes, Sf, S and S preferably of iron, which are provided with extensions S 3?" and S which rest upon conductors V V connected to the negative pole of a source of nrovmland replaced by simply lifting them out ofthe tank without disturbing the other parts, the upper extensions'I-I being at least long enough so that there will benothiug to interfere with the remo'val'of the cathode S The hopper I is hinged at i sothat it can be turned up out of the way of tbe'catlrode S. N ormally it rests against the upright t" of wood or other poor conducting material. The basket H ispermanently electrically connected by the supporting lugs H tothe conductors W W Qand the positive pole oi the source of electricity so that its contents form the anode 'in the electrolytic cell. i

- r O In Figs. 5 and 6. 1t A are detlnnmg baths dischargingtin'ned or black serap into the oonvcyer 0. The

discharge into the conveyor is slow and, if nntsteady,

is at frequent intervals. The conveyor carries the detinned scrap to the washers 1, 2, 3, each oi which has a basket similar to that in lhe bath A (Fig. -1)l The neighboring washing baskets are connected. and

through all of them runs a common conveyor K (shown only in Fig. 6). Power is applied to tlie conveyor as it comes from each washing basket throughthe wheels P P. P. Thetanks of the baths 1, 2, 3, are supplied: withrunning water, fed to the last tank at 4, and-flow- I ing through the washiug tanks in the opposite direc:

tion to the movement of the black scrap until it -flows through connections 5 and 6 and out of the first tank at 7. Each washing tank is provided with a diaphragm 8 extending clear across and as near to the bottom as the basket or tubes will permit, so as to direct the How of theiwater. By'having the \vatel-flow in the opposite direction'to the movement of tl1e crap,-thescrap first j mcetswater containinga considerable percentage of the electrolyte and as it advances meets water which is more and more pure until just hehn-e it leaves the washing tankiit passes through s 'il')stantially pure water. The tin scrap is in this way detinned and {washed-without manual labor other than that necesto iced itinto the hoppers'll V It is to he noted that there is no eleetricatcontact between the discharge ehute II" and the conveyor 0 or the material on the convey/m 0, since this coluieyer.

moves fast enough to prevent the'materlal piling up so as to touch the chute H", and further, that the con 7 other points, This is of particular importance where the electrolytic apparatus are electrically in series and mechanically in multiple as shown in Fig. 5, which is the prot'erredarrangement;

In operating the apparatus, a caustic soda solution heated to about centigrade is caused to circulate through the tank A. The tin scrap is then fed into the hopper I sulliciently fast so that the'bnsket when once filled is kept full. The conveyor chain it is then operated through the sprocket wheels P with eilher a' steady or a periodic movement, so that a substantially continuous mass of scrap. within the tank is subjected to electrolytic action for a period sufliricnt to remove all the tin therefrom. When the cathodes S, b and S are sufficiently lcoated with tin sponge, they are removed from the tank and the tin sponge removed therefrom in any suitable manner. of theltank and of the cathodes permits the substitution of a fresh cathode whenever one is,reinoverl. As the conveyor chains with theT-bars move, the scrap' as it leaves the bath is permitted to drain to a greater or less degree according tov the length of the upper 02; tension H and the. rate of movement of the chains.

In this way the greater part of the electrolyte flows immediately hack to the tank A. The form of the apparatusresults ip a comparatively slight exposure of the electrolyte to-the air, and at the same time permits The construction it to be 'easilysurrounded by a non conductor of heat;

When the tank is so surrounded, as well as the pipes conducting the electrolyte to and from the mine, as indicated at 1-1", the loss of heat by radiation is reduced to a minimum. The permanent electric connections and electro-chemical relations of the elements in the bath'are such as to make the resistance comparatively low, and thus save electrical one: y. Scrap is removed as fast as it is detinned, and fresh scrap is simultaneously introduced, so that the resistance of the bath and the Working conditions are always substantially theharne. The scrap which passes through the bath' is all subjected. to the same conditions of current and heat, being almost uniform in position with relation to the How of olectricalcun'ent and electrolyte. More over, the scrap in'going through the basket is turned upside down, permitting the escape of any'confined h air, and also a more complete-circulation of the electrolyte. The scrap, when the tin has been removed, is carried to the washers. Moreover, the scrap is inverted or reversed in position while passing through each washing tank and is also inverted or reversed in posi tion while passing through the air in going from one washing tank to another. The-emptying of the cans between each, bath insures a more complete washing of their interiors. a

The apparatus is simple, and the partscan he made of such proportions as to easily stand all. the strain necessary, and moreover, in-tho normal operatirm is:

not subject to very hard usage. This results in small cost for repairs and small danger of interruption of the work. The tin powder or sponge is deposited upon the cathode plates only, the tank itself being neutral. The refuse fails to the bottom of the tank and is therefore free from. tin powder, except as the same may be dislodged from the cathodes. i 5 My invention permits of Various themselves to those skilled in the art. The apparatus which I have show-n and described is, however, the form preferred by me.

The method herein described is claimed in a divi- .sional application filed by me on the 20th day of April, .1906 Serial-No. 312,759.

What Iclaim is: q 1. In an electrolytic detinning apparatus, the com:

conducting materialv insulated from said tank and lul'aptcd to be submerged in 'an electrolyte, means for continuously feeding tin scrap to said receiver, and automatically removing detinned scrap therefrom, a source of electri ity to one terminal of which said receiver is connected inde pendently of said scrap so as to constitute an anode, and a cathode connected to the other terminal of said source, said receiver having on its inside an exposed metallic surface with which said scrap makes :1 moving electrical contact. I

In an electrolytic detinning apparatus, the combi nu tion of a tank for containing the electrolyte, with .stal'ionllry metallic basket in said tank for containing, the

tin scrap, snitl basket being insulated from 'sz id tank, means for conveying or advancing the tin scrap through the basket, an electrode in the tank undn source of electricity having its terminals respectively. connected tosaid electrode and independently of said scrap to said.

basket having on its. inside an exposed mesuid scrap makes a moving brisket, s21 i;l]|lC,$lllf2iC with which electrical contact.

in zin electrolytic .dctinning apparatus, the combination ot :1 tank, for containing the electrolyte, with a' nected to said cathode plates and independently of aid scrap to said brisket, said basket. having; on its iusidlfan exposed metallic surface 'with which said scrapmakes a moving electrical conui' -'l.- In tin electrolytic dtinningiuppnrzltus, the combination of u tank for contuiningdhe elc.l;rol yte, with a sh'lion I (in scrap, d basket helm; insulated from said tank, menus for conveying or advancing lbc till 'ip'through the basket, :in elcclrode in the funk and a source of electric said electrode and iml'cpcmlcnlly of said scrap to s-llll basket, said l,l k beinginsulated or neutral in respect-to 'lhc electric ('lltrllil, so llllllpils wvulls will not act as (:liilljlitS for deposit of lin sponge, suid basket having; on ils inside an exposed metallic su vvilh which said p IlllkllS-FL moving cleclririrl cont .v ln n clcr'troLvlic duiiuuing app: lusf thc (zombinalion of u tnnk lor r-onlniuiur; the -olyl:e,' xvi til a 'slnliunllry mclnllir: bnskcl in said lunk lor conveying the lin scrup. said basket, being; inslllzitcil l'l'um Silili tank,'

553 means for coin vying, or :illvum'inc; the [in scrap through bnskcl wilb ului-lrnlylilzb-linniur: combb lunk l'or l-mllninlllg \vi'lll nv J iiili bzlrib' l in will lnuk l'or-rontninin l', lill bring lnwhuicll from said lunk, llm Liu S(, up through said e basket,

modifications, both. in form and in materials used, such as would. suggest binntior. of a tank, a stationary receiver composed of= 'y nu-iallic basket. in s it] tank tor cont: ning the.

exposed the brisket-jun eleclrode in the tank and a source oti 'electiic'ii.'-liaving its terminals respectively connected to ode and independently of said scrap to said n'd meansjfor returning buck into the tank the liquid dripping from the scrapafter it leaves the tank, suid'hasket having on its inside an exposed metulli fare witlri'vhicl said 'up makes a moving electr contact.

-7. in a detinniug'appurarus, the combination of a tank, for contniningihe electrolyte, with u stationary metallic basket in said tank for contzi'iim, the-tin scrap, said baskcbbeiuc; insulul'ed from said tank, :1 conveyel' fut" advancing the tin -srr2ip in and through the: bnsketfu' i-emovableczlthode plate in said tank, :1 source of elec tricity buying its terminals l'cspectiveb connectedto said basket, independently of said s ip and to sn'id cathode plate, said basket havingon it. inside an exposed metallic surface with which said scrap makes it moving electrical contact. I w

In a detinnihg; apparatus, the combination of a tank;

2\ tubular U-shaped basket contained therein, and :1 flexible conveyer passing through said blrsket, said tank helm, dapted to contain a liquid for treating the contents ulf said basket. I Y

9. ln nde'tinning uppurutu s,.the combination um tank,

a tubular U-shaped basket of conducting lnnte'rlu contuine'd therein, and a flexible conveyor pas'ing'ibrough .said'bziskeL. said tank being adapted to contain zr' liquid basket, said tank being adapted lo couluin :1 liquid for treating the contents'of said basket, an electrode lo -utcd between the upright arms or said basket, and :1 source of electricity li;1vlng terminals respectively connected to said'electrode ilnd'szrid basket.

1'1. 111 a detinning appnratus,-tlieconibinatiou'of a tank,.

:1 tubular U shuped basket of conducting materil contained therein, and a flexible conveycr p2 sing thrm grh Ibasket, said tank being adapted to contuin .a liquid for treating thecontents of said basket, electrodes on each sideotsairl basket and between the upright arms lhercul', zrnd a source of electricity having its terminals. i'esprctively connected to said electrodes and to suid'busket.

12. ln a .d'etinningapparatus, the combination of :l.

tank, il tubular U-sbllped basket contained therein, and I a flexible 'convcyer passing throiurh suid basket, suiil izink being-adapted to contain a liquid for t rculing tlre con- .tents of. said basket, and an upward extension usingon the delivery side of saidbusket.

iii. in a tlctinnin apparatus, the combination of it tank, a tubular v'fiillllltifl basket. contained therein, a convleycr pa 'ng through to contain at liquid lor id basket, said tank being :lduptlnl ng the contents of said bu un upward extension rising-.on the delivery side of said.

lnrskei. and guiding und driving wheels for said convcyel',

the llliViIl}: wheels being located near the upper end of sllill extension.

l lpln a rluiinninp; :ippurulus, the combination of n tank, nv (.ubulur U-sllnpcd basket contained therein, :1 com vuycr. p'll sing through said basket, said tank being adapted lo ronlil'lu a liquid for treating the contents of said basket, and an upward extension rising oil-the delivery side of the buskclt. I

15. for onl'ninin the electrolyte, with a metallic baskclzin sli l tzuik lor conluiniu the tin scrap,- zi conveyor for :u]

winning the tin scrap in m d lhrough the baskcl, :1' cathodeplain in said tank; ll son 1: ul cl( tricity huvingil.

In a dctinniu 'r apparatus, the combination of a tank 4. ensues funk 'iofco'ntaining the electrolyte, with a basket in said tank for containing the tin ,scrap. a conveyer for advancing the tin scrap in andtln-ough the basket, a cathode plate in said tank, a scnrcecf electricity having its \Ecr minals respectively connected to said basket independently of said scrap and to said cath'ode plate, said basket havin on its inside an exposed metallic surface with which said scrap makesa moving electrical contact, a washing tank,

a con'veyer for passing the scrap through said washing tank and a conveyer for delivering thescrap trumihe con for receiving and 'confining the scrap and advanclng ii through the tank in a suhslantialiy continuous mass, I

*ai' ihe curved portion ,thercot, and engaging with the cathode pinto in said tank, said confining, means being constructed of a conducting material and insulated from' said tank and havingan interior metallic surface adapted 2Q ioanake electrical contact with the scrap contained therein, and a source of electricity having its terininalsre speciively con-n'ccl'ed to said receiving and confining means,

independently of said scrap and also to said cathode plate.

18. In a detinning apparatus,- the combination lwith a tank for containing the electrolyte, 017.:1 tubular basket of conducting material forreceiving and confining thescrnp while in said tank, said basket being insulated from said tank,n1cans tor conveying or advancing the scrap through '30 tire tank .whiie contained or 19. In a detinnin g apparatus, the combination of a source of electric current, a plurality 0t electrolytic de' tinning baths, each having an anode consisting oi tin scrap and a cathode and arranged electrically in series with said source, a common receiving means, and a pinrality of tubular shaped baskets and conveyors arranged in multiple for passing continuous masses of ilrei'said iln iivering the same to Hold common receiving means, the

several baskets and conveyers for passing the scrap through said baths being each electrically insulated Irom every other basket and conveyer.

20. In a dctinnlng apparatus, a'comliination of a U- shaped basket, a eqnveyer therein having projections extending through the sides thereof at the curved portion of extending portions 01' said convey cs-nnd lneans toadriving said conveyer. v v i I 21. .In a detinning apparatus/the combination 0"! a U- shaped basketihnving in two opposite sides sunken gr oves, a conveyor having flexible members adapted to run in said grooves and bars passing through'the center of said asket and Joining saidimembers, and means for moving said conveyer. 7 1 f 22. in a detinning apparatus,,thecombiniotion of a tank, a ll-sliaped bas'kettherein having perforated sides but an iniperiorate bottom,; and a conveyor within said basket end meau's for movingso'id couvevor.

I MEREDITH 'Lnrrcn.

Witnesses: E 

